The elliptical shape of the hull and turret castings are easily seen in this frontal view. This tank is fitted with a T-shaped muzzle brake. The right-hand aperture for the stereoscopic rangefinder is visible on the turret side below the commander's cupola, and the gunner's telescope T156E1 would peer through the hole in the gun shield. (Picture courtesy Calvin.)
The large box in the middle of the hull rear plate housed an infantry phone. The square plates below and outboard of the phone box and the central circular plate just below the phone box were all for access to the transmission. Note that this tank has had its track tensioning idlers removed from behind the rear road wheels.
The M48 and M48A1 had their exhausts routed through the rear deck, and the exhaust outlet is visible here. Deflectors were necessary to keep the hot exhaust gases from heating the gun travel lock, a situation which would eventually cause it to bind. The armored cover in the foreground protected the engine oil filler.
The drivers of M48s had a small hatch compared with later versions of the tank. This vehicle had been equipped with an infrared periscope for the driver; the IR periscope was mounted in the hatch door.
The driver was provided with an escape hatch in the hull floor below his seat, the opening for which is shown here. Near the rear of the hull, we can see the two fuel tank drain hole covers mounted side-by-side, the main engine oil filter access hole cover behind these on the tank's left, then the main engine drain hole cover behind this.
The positioning of the gun travel lock in relation to the exhaust and how the deflectors protect it can be better seen in this image. A fuel filler cover is visible in the lower right.
Due to the prodigious thirst of its carbureted V12 engine, an auxiliary engine was provided to power a 28 volt, 300 ampere generator when the main engine was not needed. The muffler for this engine was mounted on the right fender just aft of the turret.
The commander of the M48 was provided with a conventional cupola and an external mount for his .50cal machine gun. This was replaced in production with Aircraft Armaments's M1 cupola.
The turret roof is shown here, with the commander's cupola on the left facing away from the camera. The loader's hatch is beside the commander's cupola.
The loader's hatch is highlighted here.
A ventilator was mounted in the turret to the loader's left rear. Antenna mounts can also be seen in front of the ventilator and at the turret rear.
The cupola is shown here from the rear. The commander was provided with four periscopes in the cupola, including one in the hatch door. The cupola provided the commander the capability to aim and fire--but not reload--the .50cal machine gun from under armor. Note that the door catch is welded to the periscope guard.
The front view of the cupola provides details of the gearing used to aim the machine gun.
More details of the cupola mount for the .50cal machine gun can be seen here. If necessary to reload the machine gun from under armor, the commander could unlock the mount from the cupola and then crank it to the left so that the loader could gain access to the ammunition box. The mount was then cranked back into position and secured from inside the cupola. The guard for the gunner's M20-series periscope is in front of the commander's cupola.
When not in use, the machine gun mount could be stowed on a bracket welded to the turret roof in front of the loader.
The inboard side of the machine gun mount stowage bracket is shown here.
The gunner's controls are shown here. Power traverse and elevation were accomplished by the single control handle: twisting it to the right or left traversed the turret, and the handle was rotated on the axis perpendicular to the gun to elevate the ordnance. The top of the handle was pushed forward to depress the gun, or pulled towards the gunner to elevate the gun. The manual traverse handle is out of view to the right of the image. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
The commander was provided with a similar turret control handle as the gunner, except that the commander's had an override lever that would allow him to take control away from the gunner. The commander lacked the gun selector switches available to the gunner, however, so it was necessary for the gunner to have the appropriate weapon selected before the commander could fire from his position. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
The fire control system diagrammed here. 1. Equilibrator. 2. Spare lamp box. 3. Elevation and azimuth boresight knobs. 4. Light switches and brightness control. 5. ICS knob. 6. Range scale. 7. Filter lever. 8. Range knob. 9. Range input shaft. 10. Superelevation output shaft. 11. Manual range crank. 12. Ballistic correction knob. 13. Superelevation scale. 14. Ammunition selection scale. 15. Reset switch. 16. Ammunition selection handle. 17. Ammunition cam access cover. 18. Circuit breaker. 19. Spare cam box. 20. Range dial. 21. Elevation Quadrant, M12. 22. Ballistic Drive, T24E2. 23. Telescope, T156E1. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
The eyepieces of the rangefinder T46E1 are shown here. The interpupillary knob adjusted the eyepieces so that they could be from 58-72mm (2.3-2.8") apart. The halving knob allowed adjustment of the right-side ranging reticle when it appeared at a different elevation from the left reticle. The ICS (internal correction system) knob allowed the individual commander to adjust an individual rangefinder to his personal vision and use. He would select a target of known range and then use the ICS knob if necessary to correct the rangefinder reading until it was accurate. Ten rangings were averaged to obtain that commander's ICS setting for that rangefinder. The range scale moved when the range knob was turned; the range knob adjusted the apparent movement of the ranging reticle or indexed a given range on the range scale. The filter lever introduced or withdrew filters into view. The T46E1's base length was 79" (200cm), it was graduated from 400 to 4,800 yards (460 to 4,400m), and it had 10x magnification with a 71-mil field of view. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
A closeup of the armored blister protecting the right-hand aperture of the stereoscopic rangefinder T46E1 is shown here.
The principle of the stereoscopic rangefinder is diagrammed here. The five marks would show in the eyepieces of the rangefinder, and when properly adjusted the reticle would appear so that the upper bars are closest and the lowest bar is farthest away. The commander used the range knob to adjust the reticle so that the lowest bar appeared to be as far away as the target. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
The T31 was an electromechanical ballistic computer that took range data from the rangefinder T46E1, applied this to ammunition and ballistic corrections entered manually by the gunner, and produced the correct superelevation for the 90mm gun, which was adjusted into the gunner's periscope and rangefinder by the ballistic drive T24E2. The gunner then was able to put the aiming cross onto the target with the correct superelevation applied. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
The glacis of the M48C was marked with a prominent weld bead to prevent confusion with tanks that were armored to the correct specification. (Photo by Richard S. Eshleman.)
The top of the turret is shown here in splendid detail. Both the loader's D-shaped hatch and the commander's cupola hatch are open. The openings for the periscopes in the commander's hatch door and the front of the cupola can be seen. (Photo by Richard S. Eshleman.)
The large cupola, five return rollers, and rear auxiliary track tensioning wheel identify this vehicle as an M48A1 or M48A2 tank. The shock absorbers on the first two and last road wheels can be seen, and stowage boxes are present on the fenders. The turret ventilating blower cover can be seen on the top of the turret rear, just in front of the stowage basket. A mount for a water can is placed low on the turret rear. A grab rail is welded to the turret below the lifting eye. The left armored blister for the stereoscopic rangefinder is near the middle of the upper side of the turret.
The ventilator in the turret's left rear can be seen, and the structure of the turret basket and water can mounts on the turret sides are apparent.
The grille doors toward the rear of the tank were for transmission access, while those to either side of the exhaust provided access to the engine. The gun travel lock is folded down onto the transmission access center plate. Numerous lifting eyes are present to enable the various grilles and plates to be swung open.
The right-side transmission and engine access grilles can be seen here, as well as a closer view of the gun travel lock in the stowed position. As above, the cover next to the gun travel lock protected the engine oil filler.
The M48 and M48A1 had two gasoline-powered personnel heaters installed along the left side of the hull. The exhausts for these heaters were routed through the front hull next to the driver's hatch as seen here. The guard in front of the heater exhausts housed handles for external activation of the vehicle's fire extinguishers. Around the gun shield are mounts for a cover, and through the gun shield are protrusions for the coaxial machine gun (on the cannon's left), and the gunner's direct sight telescope on the opposite side of the main gun.
The Aircraft Armaments cupola is sketched here, with the rear hatch in the open position. The aperture for the turret-type M2HB machine gun can be seen, as well as the vision blocks around the base and the periscope guard on top. The cupola was 14.875" (37.783cm) tall without the periscope, 38.375" (97.473cm) in diameter, 48.8125" (123.384cm) long without the machine gun, and weighed 1,400lb (635kg). (Picture from TM 9-1005-219-35.)
When fitted to tanks manufactured with the large driver's hatch, an adapter ring (labeled "6" in the image) was necessary to mount the cupola to the turret flange. The ring assembly increased the height to 16.4375" (41.7513cm) without the sight, the diameter to 41" (104cm), and the weight to 1,670lb (758kg). (Picture from TM 9-1005-219-35.)
The outline of the door in the rear of the commander's cupola can be seen in this image, and its hinge is at the bottom next to one of the covered vision blocks. Five vision blocks ringed the bottom of the cupola, and the commander was provided with a periscope M28 in the top for using the machine gun, which was fed from a 100-round box magazine. The cupola was provided with an interlock so that the commander secure it into alignment with the main gun, which then allowed the cupola periscope to be used as an auxiliary target designation means.
The interior of the commander's cupola is shown here. The interlock that allowed the cupola to remain aligned with the turret is labeled as the detent lock. Note that the machine gun is mounted on its left side, and the ammunition box has been omitted in the image. (Picture from FM 17-79 Tank, 90-mm Gun, M48.)
The thickness and contour of the main gun shield can be gleaned from this picture. Lifting eyes were welded to the upper corners, attachments for a canvas cover can be seen on the turret, and the aperture for the gunner's T156E1 telescope is below the lifting eye.
Details of the muzzle brake and bore evacuator on the 90mm gun M41 are provided here.
The auxiliary generator muffler is present on this tank.
The auxiliary track tensioning idler and its swing arm are highlighted here. Note that it is mounted in a different way with a longer swing arm compared to those found on the M46 and M47 tanks. The attachment for the rear shock absorber can be seen just in front of the bump stop for the rear road wheel.
The final drives of the medium tanks from the M26 Pershing have slowly been rotating upwards, finally making it to the horizontal in the M48.
This M48A2C features three track return rollers, and lacks the small track tensioning idler previously found between the last road wheel and drive sprocket. The most important changes are internal, however, and included a new coincidence rangefinder and other fire control system improvements. One of the rangefinder sights is visible on the top side of the turret.
The elliptical cross-section of the tank can be seen in this view. A Y-shaped blast deflector is apparent, as are the two sighting blisters for the M17 coincidence rangefinder on the top of the turret sides. The single exhaust for the personnel heater is visible to the right of the driver's hatch, and the three periscope housings surrounding his hatch are closed. The driver's hatch itself has a mount for an infrared periscope. Just to the left of the driver's hatch is a support for when it is rotated to the open position. The large M1 commander's cupola dominates the turret's right side, and the guard for the gunner's M32 periscope is visible in front of the TC's cupola. The opening for the coaxial machine gun has been plated over on the gun shield's left side, and the larger aperture for the gunner's M97C telescope is on the other side of the 90mm gun.
The difference between the small driver's hatch in the tank above is easily contrasted with the hatch on this later model.
The new exhaust grille is obvious when the vehicle is viewed from behind. The square in the right-side door is for mounting a deep-water fording exhaust stack. The vehicle's taillights are just below the exhaust grille doors, and a towing pintle is placed in the center of the lower rear plate. The two square plates and the circular plate above the towing pintle still provide access to the transmission. The ventilator is also visible on the turret's left side, and a periscope guard rises up from the commander's cupola. The housing for the infantry telephone intercom can be seen on the right fender.
This tank lacks the track tensioning idler wheel found on the earlier Patton tanks. The number of track return rollers has also been reduced to three. The frame for the insulated exhaust tunnel is visible, and engine intake grilles line both sides of the exhaust tunnel. The friction snubber on the last road wheel is also apparent, just in front of the return roller.
The clamshell nature of the commander's cupola can be seen in this image, where both the commander's and loader's hatches are open to the rear. These troops were part of the 3d Brigade, 1st Infantry Division and were taking part in Operation Buckskin near Laike, Repblic of Vietnam. (Picture taken 8 Jan 1966; available from the National Archives.)
The commander's cupola on this tank sits atop the vision block adapter ring, giving the TC more room and a better all-around view. The exhaust for the M60-type personnel heater can be seen just in front of the fender stowage box. The aperture visible in the gun shield was for the gunner's direct-sight telescope.
This tank is provided with a xenon searchlight, and details of its mounting are visible here. The tubular guard in front the commander's cupola is to prevent the TC from machine gunning the searchlight. The gunner's periscope is visible between the searchlight guard and the commander's cupola.
Once in action in Vietnam, some tank commanders felt that the cupola did not provide sufficient room to service the machine gun. Despite the increased exposure to enemy fire, external mounts were devised for the .50cal, as on this machine. This tank, from H Company, 2nd Battalion, 5th Marines, was fitted with the cupola vision block ring but retained the original style headlights. (Picture taken 20 May 1970 by Cpl G.N. Zimmerman; available from the National Archives.)
From this angle, the M48A5 can be difficult to discern from the M60, but the commander's cupola shape and number of return rollers can help our identification. The armor framing along the tops of the exhaust louvres and armored boxes around the taillights that first appeared on the M48A3 (Mod B) are visible in this rear view, and the raised position of the infantry telephone can be contrasted with this image. (Photo by Richard S. Eshleman.)
This M48A5 is sporting the Israeli-designed low-silhouette commander's cupola, and the stark contrast between the two designs is apparent when this vehicle is compared with the tank above. The bore evacuator of the 105mm gun M68 is visible, as is the right-hand "eyeball" of the coincidence rangefinder near the center of the turret. The taller box just behind the long fender stowage box is an engine air cleaner housing. The xenon searchlight is not plugged in to its power receptacle on the turret roof. A .50cal machine gun is mounted on the commander's cupola; the low-profile cupola usually sported a 7.62mm M60D machine gun. This tank was fitted with the later headlights first found on the M48A3 (Mod B), and their brush guards can be contrasted with the tanks above.
The engine intake grille doors are open on this vehicle, and the commander's cupola hatch arms can be seen as well.
The loader was provided with two mounts for his M60D machine gun, and both are visible in this image. The power receptacle for the tank's searchlight can also be seen in front of the TC's cupola.
A closer look at the low-silhouette commander's cupola is provided here. The positioning of the three periscopes in the cupola housing can be seen in front and to the sides of the hatch door, and the details of the machine gun mount can be gleaned as well. The springs of the loader's hatch door are in the background. The cupola weighed 340kg (750lb) and its height was 24cm (9.4") above the hull roof. (Photo by Richard S. Eshleman.)
This tank is from C Company, 3/161 Armor, and features the low-silhouette cupola and M60D machine guns. The loader's weapon is situated on the roof mount to the front of his hatch. The crew was being assessed on Tank Table VIII, and an evaluator is sitting on the turret. (Photo by Rob Coach.)
Another view of the loader's machine gun in the forward mount is provided here. The grips are protruding a bit into his hatch opening. (Photo by Rob Coach.)
This tank has also been fitted with the M48A5PI features, including the increased ammunition stowage. Nine rounds were stowed in the left side of the turret bustle behind the loader.
In front of the loader's position, to the left of the main gun, is a nineteen-round ready rack. This tank is fitted out with replica HEAT and sabot ammunition.
Above the 105mm ready rack is the coaxial machine gun ready ammunition box, which could hold 2200 rounds. The feed chute can be seen towards the front of the box, and the cradle for the coaxial machine gun is visible to the right of the picture.
An overview of the driver's position is seen here. He used the black steering wheel to control direction, and the brake and accelerator pedals are below the wheel to the left and right, respectively. The red bottles are fire extinguishers, and the green tube to the front of the driving compartment is the crew heater. The lever to the driver's left in front of the fire extinguisher bottles is the purge pump, and the pump handle to the right of the driver's seat is the turret seal pump. The transmission shifting control lever is marked for park, neutral, and low, high, and reverse ranges. Between the accelerator pedal and the transmission shifting control lever is the throttle lock lever.
When in reverse, turning the steering wheel to the right caused the vehicle's rear to swing to the left, and vice-versa. When in neutral, the tank would pivot to the right or left by turning the wheel in the desired direction.
The left side of the driver's compartment is highlighted here. The dimmer switch is labeled, and the red fire extinguisher control handle can be seen towards the vehicle's front. Twelve main gun rounds were stowed in the green tubes behind the fire extinguisher bottles, and a nine-round rack was placed on the right side of the driver's compartment.
The right side of the tank commander's position is shown here. His control handle allowed him to operate the turret and weapons, and the green boxes are the vehicle's intercom controls.
The eyepiece for the M17B1C rangefinder is found in the forward area of the commander's station. Just below the eyepiece is the occluder knob, and the large black knob below and to the right is the ranging knob. The halving knob is located just above the ranging knob, and above and to the right is the filter lever. The red knob above the eyepiece is the ICS knob, and the range scale window can just be seen to the right of the ICS knob. Two of the three periscopes in the TC's cupola are visible in this shot.
Above the main gun is positioned the instrument light panel for the rangefinder. The farthest-left knob dimmed or brightened the range scale, the knob to its right was for dimming or brightening the reticle, and the switch toggled the coincidence and auxiliary gunsights. The next knob to the right is the vertical adjustment knob, and the final knob in the picture is the horizontal adjustment knob. The shaft going forward from the bottom of the rangefinder is the ballistics drive link assembly, part of the ballistic drive that attached the gun mount elevation system, gunner's sight, commander's telescope, and ballistic computer.
The gunner's controls are shown here. Powered traverse and elevation were accomplished by the control handles in the center of the picture. The black manual elevating handle is located behind the control handles, and the red button on this handle is the gun firing button. The white handle above the control handles was for hand traversing the turret. The red handle on the left side of the picture was for manually firing the main gun. From left to right, the selector switchbox to the front of the tank activated the coaxial machine gun, the main gun, and turret power. Just below the selector switchbox is the gunner's relay box, and the superelevation actuator is just to the switchbox's right. The gauge behind the gunner's control assembly showed the accumulator pressure. The device to the right of the picture with knobs and dials is the M13B1C ballistic computer, and the gunner's dial-like azimuth indicator is just beyond this. A green intercom control box is below the azimuth indicator. The container below the gunner's control assembly is an oil reservoir.